1. Field of the Invention
The present invention relates to a guidewire extension wire and connector assembly for connecting to a proximal end of an initially inserted guidewire. The connector assembly can be broken to detach the guidewire extension wire leaving a cylindrical stub section identical to the proximal end of the initially inserted guidewire whereby another, e.g. different length guidewire extension wire and connector assembly, can be connected to the cylindrical stub section.
2. Description of the Related Art Including Information Disclosed Under 37 CFR .sctn..sctn.1.97-1.99
Heretofore, a number of guidewire extension wire connector assemblies have been proposed. Several examples of such previously proposed guidewire extension wire connector assemblies are disclosed in the following U.S. Patents:
______________________________________ U.S. Pat. No. Patentee ______________________________________ 4,827,941 Taylor et al. Re 34,466 Taylor et al. 4,875,489 Messner et al. 4,907,332 Christian et al. 4,917,103 Gambale et al. 4,922,923 Gambale et al. 4,966,163 Kraus et al. 5,031,636 Gambale et al. 5,035,686 Crittenden et al. 5,060,660 Gambale et al. S,109,867 Twyford 5,113,872 Jahrmarkt et al. 5,117,838 Palmer et al. 5,133,364 Palermo et al. 5,139,032 Jahrmarkt et al. 5,163,903 Crittenden et al. 5,188,621 Samson et al. 5,191,888 Palmer et al. 5,195,53S Shank 5,195,978 Schiffer 5,197,486 Frassica 5,234,002 Chan 5,234,407 Teirstein et al. 5,246,009 Adams 5,247,942 Prather et al. 5,255,690 Keith et al. 5,267,573 Evans et al. 5,269,759 Hernandez et al. 5,271,41S Foerster et al. 5,275,173 Samson et al. 5,281,203 Ressemann 5,282,478 Fleischhaker, Jr. et al. ______________________________________
These patents describe various types of connector assemblies for connecting an extension guidewire to an initially inserted guidewire. For example:
The Taylor et al. U.S. Pat. No. 4,827,941 and Reissue No. 34,466 show an initially inserted guidewire having a smaller diameter proximal end which is shaped in an undulating or sinusoidal shape. An extension guidewire is provided having a hollow tubing at a distal end. The tapered undulating end of the initially inserted guidewire is inserted within the hollow tubing of the extension guidewire. A friction fit between the tapered undulating section and inner walls of the hollow tubing securely hold the guidewire and extension guidewire in place. The friction fit connection so formed permits the joined guidewires to be separated simply by pushing the guidewires toward each other and then pulling them apart.
The Messner et al. U.S. Pat. No. 4,875,489 shows an extendable guidewire having main and auxiliary sections and a connection which permits the two sections to be joined together and separated simply by pushing the two sections together and pulling them apart. The initially inserted guidewire has a tapered proximal end and the auxiliary section has a connector at a distal end having an inner tubular member and an outer tubular member or sleeve. The tapered proximal end of the main section is inserted within the inner tubular member of the auxiliary section.
The Foerster et al. U.S. Pat. No. 5,271,415 shows a guidewire extension system for connecting an extension wire to a guidewire. The system includes a tubular outer body with a guidewire retention element and an extension wire retention element fixed within the outer body. The retention elements are preferably helically wound wire and form both a right handed thread and a left handed thread within the outer body. The guidewire and extension wire each have tapered ends and a reduced in diameter core and a flattened tip. The tips are threaded into the helical wire in the outer body until the tips from the guidewire and extension wire abut inside the core.
The Schiffer U.S. Pat. No. 5,195,978 discloses a rapid exchange over the wire catheter with a breakaway feature. The catheter has a breakaway element for progressively exposing the guidewire from a proximal end toward a distal end of the catheter in a simple and efficient manner. The breakaway element may be formed as a longitudinally aligned pull strip provided in the catheter guidewire. In an alternative embodiment of the catheter, the catheter is formed of one more tubular segments which are aligned linearly and joined at circumferential tear lines. A segment of the catheter can be broken away from am adjacent segment at one of the circumferential tear lines and then pulled away from the guidewire and discarded. Removal of subsequent portions of the catheter by breaking segments at one of the circumferential tear lines can be repeated until the remaining part of the catheter can be removed without disturbing the position of the guidewire within the person's body.